This paper explores deep insights into sustainability transition tensions and pathways in terms of place-based conflict and potential for synergies between offshore wind energy (OWE) development and justice for humans and nonhuman nature. Specifically, we build a capability and recognition-based multispecies blue justice framework that at once centers ecological reflexivity (i.e., environmental awareness-raising, proxy representation of nature, and institutional recognition and protection of rights of nature and human-nature relationality), decenters anthropocentric frames of justice, and sheds light on injustices, human and nonhuman that climate and energy transitions may create or reinforce. This framework then informs analysis of a sustainability transition conflict, specifically a longstanding OWE conflict on Hiiumaa island, Estonia. This analysis unravels justice concerns, human and nonhuman, raised by proxy representatives of nature (i.e., grassroots actors and environmental stewards), the knowledge contestations involved, and the resolution measures undertaken thus far. Next, we discuss the possible transformative role of the OWE conflict, including how a Supreme Court ruling invalidating the OWE plan has fostered reflexive planning and may have set a legal precedent that may have human and nonhuman justice implications for the handling of future planning cases. We then highlight remaining challenges for socially and ecologically responsive OWE deployment. These include the judicial non-recognition of nature’s right as well as environmental values and sociocultural ties to nature as rights worth protecting, and the likely effects that formalization of European Union ambitions to speed-up and ramp-up renewable energy could have locally. These include prospects for environmental stewards and ocean defenders to steer nature-positive, people-centered energy transitions. Last, we propose conditions for enhanced multispecies justice, including how formal interventions (e.g., law) and informal practices (e.g., negotiation, awareness-raising) can be harnessed to unlock productive conflict and align energy transitions with the norms of justice, human and nonhuman.